PinchHandler works unreliably with Wayland

Using a PinchHandler on a simple Rectangle to pinch-zoom and pinch-rotate does not work reliably when the sample app is run in e.g. the minimal-qml QtWayland Compositor. Sometimes the pinch is triggered but most times not.

I was not able to test this with a non-Qt Wayland Compositor but expect similar behaviour.

Other PointerDeviceHandlers handling only one touch point work fine with (Qt-)Wayland.

Running the sample app directly on X11 provides smooth handling in the PinchHandler.

A PinchArea does also work smootly when the sample app is run with Wayland.